Markus M. J. Nielen

Markus M. J. Nielen

*This is an algorithmically generated author record based on publicly available information.

Current Organizations / Institutes

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Previous Organizations / Institutes

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Markus M. J. Nielen has a total of 124 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • ASO Visual Abstract: The Impact of Best Practice Meetings on Outcomes of Esophageal Cancer Surgery in the Netherlands

    by Maurits R. Visser, Tessa C. M. Geraedts, Markus M. J. Nielen, Suzanne S. Gisbertz, Jelle P. Ruurda, M. W. Wouters, Richard van Hillegersberg, Grard A. P. Nieuwenhuijzen, Mark I. van Berge Henegouwen, Marc J. van Det, et al.

  • Open Access

    Association between socioeconomic status and postoperative outcomes after esophagectomy within a universal healthcare system: a nationwide population-based cohort study

    by Lars van de Sanden, Teun J.L. Smits, Koen C.G.P. van de Ven, Grard A.P. Nieuwenhuijzen, Sjoerd M. Lagarde, Mark M.J. Nielen, Bas P.L. Wijnhoven, Misha D.P. Luyer, Suzanne S. Gisbertz, Richard van Hillegersberg, et al.

  • Open Access

    Koppeling van kwaliteitsregistraties en CBS-microdata in de zorg: mogelijkheden, uitdagingen en aanbevelingen

    by Daniëlle J. M. Koornneef, Sylvia Brinkman, Nicolette F. de Keizer, Saskia Houterman, Mark M. J. Nielen, Alicia Uijl, Ferishta Bakhshi-Raiez

  • Open Access

    Cost-effectiveness of a stepwise cardiometabolic disease prevention program: results of a randomized controlled trial in primary care

    by Daphne M. Stol, Eelco A. B. Over, Ilse F. Badenbroek, Monika Hollander, Mark M. J. Nielen, Roderik A. Kraaijenhagen, François G. Schellevis, Niek J. de Wit, G. Ardine de Wit

    Background: Cardiometabolic diseases (CMD) are the major cause of death worldwide and are associated with a lower quality of life and high healthcare costs. To prevent a further rise in CMD and related healthcare costs, early detection and adequate management of individuals at risk could be an effective preventive strategy. The objective of this study was to determine long-term cost-effectiveness of stepwise CMD risk assessment followed by individualized treatment if indicated compared to care as usual. A computer-based simulation model was used to project long-term health benefits and cost-effectiveness, assuming the prevention program was implemented in Dutch primary care. Methods: A randomized controlled trial in a primary care setting in which 1934 participants aged 45–70 years without recorded CMD or CMD risk factors participated. The intervention group was invited for stepwise CMD risk assessment through a risk score (step 1), additional risk assessment at the practice in case of increased risk (step 2) and individualized follow-up treatment if indicated (step 3). The control group was not invited for risk assessment, but completed a health questionnaire. Results of the effectiveness analysis on systolic blood pressure (− 2.26 mmHg; 95% CI − 4.01: − 0.51) and total cholesterol (− 0.15 mmol/l; 95% CI − 0.23: − 0.07) were used in this analysis. Outcome measures were the costs and benefits after 1-year follow-up and long-term (60 years) cost-effectiveness of stepwise CMD risk assessment compared to no assessment. A computer-based simulation model was used that included data on disability weights associated with age and disease outcomes related to CMD. Analyses were performed taking a healthcare perspective. Results: After 1 year, the average costs in the intervention group were 260 Euro higher than in the control group and differences were mainly driven by healthcare costs. No meaningful change was found in EQ 5D-based quality of life between the intervention and control groups after 1-year follow-up (− 0.0154; 95% CI − 0.029: 0.004). After 60 years, cumulative costs of the intervention were 41.4 million Euro and 135 quality-adjusted life years (QALY) were gained. Despite improvements in blood pressure and cholesterol, the intervention was not cost-effective (ICER of 306,000 Euro/QALY after 60 years). Scenario analyses did not allow for a change in conclusions with regard to cost-effectiveness of the intervention. Conclusions: Implementation of this primary care-based CMD prevention program is not cost-effective in the long term. Implementation of this program in primary care cannot be recommended. Trial registration: Dutch Trial Register NTR4277, registered on 26 November 2013


  • Open Access

    Intermediate weight changes and follow-up of dietetic treatment in primary health care: an observational study

    by Lisa D. M. Verberne, Chantal J. Leemrijse, Markus M. J. Nielen, Roland D. Friele

    Background: Primary health care data have shown that most patients who were treated for overweight or obesity by a dietitian did not accomplish the recommended treatment period. It is hypothesised that a slow rate of weight loss might discourage patients from continuing dietetic treatment. This study evaluated intermediate weight changes during regular dietetic treatment in Dutch primary health care, and examined whether weight losses at previous consultations were associated with attendance at follow-up consultations.Methods: This observational study was based on real life practice data of overweight and obese patients during the period 2013–2017, derived from Dutch dietetic practices that participated in the Nivel Primary Care Database. Multilevel regression analyses were conducted to estimate the mean changes in body mass index (BMI) during six consecutive consultations and to calculate odds ratios for the association of weight change at previous consultations with attendance at follow-up consultations.Results: The total study population consisted of 25,588 overweight or obese patients, with a mean initial BMI of 32.7 kg/m2. The BMI decreased between consecutive consultations, with the highest weight losses between the first and second consultation. After six consultations, a mean weight loss of − 1.5 kg/m2was estimated. Patients who lost weight between the two previous consultations were more likely to attend the next consultation than patients who did not lose weight or gained weight.Conclusions: Body mass index decreased during consecutive consultations, and intermediate weight losses were associated with a higher attendance at follow-up consultations during dietetic treatment in overweight patients. Dietitians should therefore focus on discussing intermediate weight loss expectations with their patients.


  • Open Access

    Opportunistic screening versus usual care for detection of atrial fibrillation in primary care: cluster randomised controlled trial

    by Steven B Uittenbogaart, Nicole Verbiest-Van Gurp, Wim A M Lucassen, Bjorn Winkens, Mark Nielen, Petra M G Erkens, J André Knottnerus, Henk C P M van Weert, Henri E J H Stoffers

    Objective To investigate whether opportunistic screening in primary care increases the detection of atrial fibrillation compared with usual care. Design Cluster randomised controlled trial. Setting 47 intention-to-screen and 49 usual care primary care practices in the Netherlands, not blinded for allocation; the study was carried out from September 2015 to August 2018. Participants In each practice, a fixed sample of 200 eligible patients, aged 65 or older, with no known history of atrial fibrillation in the electronic medical record system, were randomly selected. In the intention-to-screen group, 9218 patients eligible for screening were included, 55.0% women, mean age 75.2 years. In the usual care group, 9526 patients were eligible for screening, 54.3% women, mean age 75.0 years. Interventions Opportunistic screening (that is, screening in patients visiting their general practice) consisted of three index tests: pulse palpation, electronic blood pressure measurement with an atrial fibrillation algorithm, and electrocardiography (ECG) with a handheld single lead electrocardiographic device. The reference standard was 12 lead ECG, performed in patients with at least one positive index test and in a sample of patients (10%) with three negative tests. If 12 lead ECG showed no atrial fibrillation, patients were invited for more screening by continuous monitoring with a Holter electrocardiograph for two weeks. Main outcome measures Difference in the detection rate of newly diagnosed atrial fibrillation over one year in intention-to-screen versus usual care practices. Results Follow-up was complete for 8874 patients in the intention-to-screen practices and for 9102 patients in the usual care practices. 144 (1.62%) new diagnoses of atrial fibrillation in the intention-to-screen group versus 139 (1.53%) in the usual care group were found (adjusted odds ratio 1.06 (95% confidence interval 0.84 to 1.35)). Of 9218 eligible patients in the intention-to-screen group, 4106 (44.5%) participated in the screening protocol. In these patients, 12 lead ECG detected newly diagnosed atrial fibrillation in 26 patients (0.63%). In the 266 patients who continued with Holter monitoring, four more diagnoses of atrial fibrillation were found. Conclusions Opportunistic screening for atrial fibrillation in primary care patients, aged 65 and over, did not increase the detection rate of atrial fibrillation, which implies that opportunistic screening for atrial fibrillation is not useful in this setting. Trial registration Netherlands Trial Register No NL4776 (old NTR4914).


  • Open Access

    Effectiveness of a stepwise cardiometabolic disease prevention program: Results of a randomized controlled trial in primary care

    by Daphne M. Stol, Ilse F. Badenbroek, Monika Hollander, Mark M.J. Nielen, Roderik A. Kraaijenhagen, François G. Schellevis, Niek J. de Wit


  • Open Access

    Estimating Morbidity Rates Based on Routine Electronic Health Records in Primary Care: Observational Study

    by Mark M J Nielen, Inge Spronk, Rodrigo Davids, Joke C Korevaar, René Poos, Nancy Hoeymans, Wim Opstelten, Marianne A B van der Sande, Marion C J Biermans, Francois G Schellevis, et al.

    Journal of Medical Internet Research - International Scientific Journal for Medical Research, Information and Communication on the Internet #Preprint #PeerReviewMe: Warning: This is a unreviewed preprint. Readers are warned that the document has not been peer-reviewed by expert/patient reviewers or an academic editor, may contain misleading claims, and is likely to undergo changes before final publication, if accepted, or may have been rejected/withdrawn. Readers with interest and expertise are encouraged to sign up as peer-reviewer, if the paper is within an open peer-review period. Please cite this preprint only for review purposes or for grant applications and CVs (if you are the author). Background: Routinely recorded electronic health records (EHRs) from general practitioners (GPs) are increasingly available and provide valuable data for estimating incidence and prevalence rates of diseases in the population. Objective: This paper describes how we developed an algorithm to construct episodes of illness based on EHR data to calculate morbidity rates. Methods: The algorithm was developed in discussion rounds with two expert groups and tested with data from NIVEL Primary Care Database, which consisted of a representative sample of 219 general practices, covering a total population of 867,140 listed patients in 2012. Morbidity data were used from EHRs in the period 2010-2012, including recorded ICPC coded episodes of care, encounters and prescriptions. Results: All 685 symptoms and diseases of ICPC-1 were categorized as acute symptoms/diseases, long-lasting reversible diseases, and chronic diseases. Based on knowledge of the duration of a disease, for each category an algorithm was developed to construct episodes of illness. Compared with recorded episodes of care, for acute and long-lasting diseases, applying the algorithm resulted in a reduction of both the number and average duration of the episodes up to 53% and 94%, respectively. On the other hand, for chronic diseases, the algorithm resulted in a slight increase in the number of episodes as well as the episode duration. Conclusions: An algorithm was developed to construct episodes of illness based on routinely recorded EHR data to estimate morbidity rates. The algorithm constitutes a simple and uniform way of using EHR data and can easily be applied in other registries.


  • Top Cited Papers
    Open Access

    Calculating incidence rates and prevalence proportions: not as simple as it seems

    by Inge Spronk, Joke C. Korevaar, René Poos, Rodrigo Davids, Henk Hilderink, François G. Schellevis, Robert A. Verheij, Mark M. J. Nielen

    Incidence rates and prevalence proportions are commonly used to express the populations health status. Since there are several methods used to calculate these epidemiological measures, good comparison between studies and countries is difficult. This study investigates the impact of different operational definitions of numerators and denominators on incidence rates and prevalence proportions. Data from routine electronic health records of general practices contributing to NIVEL Primary Care Database was used. Incidence rates were calculated using different denominators (person-years at-risk, person-years and midterm population). Three different prevalence proportions were determined: 1 year period prevalence proportions, point-prevalence proportions and contact prevalence proportions. One year period prevalence proportions were substantially higher than point-prevalence (58.3 - 206.6%) for long-lasting diseases, and one year period prevalence proportions were higher than contact prevalence proportions (26.2 - 79.7%). For incidence rates, the use of different denominators resulted in small differences between the different calculation methods (-1.3 - 14.8%). Using person-years at-risk or a midterm population resulted in higher rates compared to using person-years. All different operational definitions affect incidence rates and prevalence proportions to some extent. Therefore, it is important that the terminology and methodology is well described by sources reporting these epidemiological measures. When comparing incidence rates and prevalence proportions from different sources, it is important to be aware of the operational definitions applied and their impact.


  • Open Access

    The value of joint ultrasonography in predicting arthritis in seropositive patients with arthralgia: a prospective cohort study

    by Marian H. van Beers-Tas, Annelies B. Blanken, Mark M. J. Nielen, Franktien Turkstra, Conny J. van der Laken, Marlies Meursinge Reynders, Dirkjan van Schaardenburg

    The value of joint ultrasonography (US) in the prediction of clinical arthritis in individuals at risk of developing rheumatoid arthritis (RA) is still a point of debate, due to varying scanning protocols and different populations. We investigated whether US abnormalities assessed with a standard joint protocol can predict development of arthritis in seropositive patients with arthralgia. Anti-citrullinated protein antibodies and/or rheumatoid factor positive patients with arthralgia, but without clinical arthritis were included. US was performed at baseline in 16 joints: bilateral metacarpophalangeal 2–3, proximal interphalangeal 2–3, wrist and metatarsophalangeal (MTP) joints 2–3 and 5. Images were scored semi-quantitatively for synovial thickening and for positive signs on power Doppler (PD). Association between US abnormalities and arthritis development at the joint and at the patient level was evaluated. Also, we investigated the added value of US over clinical parameters. Out of 163 patients who underwent US examination, 51 (31%) developed clinical arthritis after a median follow-up time of 12 (interquartile range 5–24) months, of which 44 (86%) satisfied the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for RA. US revealed synovial thickening and PD in at least one joint in 49 patients (30%) and 7 patients (4%), respectively. Synovial thickening was associated with both development and timing of clinical arthritis in any joint (patient level) when MTP joints were excluded from the US assessment (odds ratio 6.6, confidence interval (CI) 1.9–22), and hazard ratio 3.4, CI 1.6–6.8, respectively, with a mean time to arthritis of 23 versus 45 months when synovial thickening was present versus not present). There was no association between US and arthritis development at the joint level. Predictive capacity was highest in the groups with an intermediate and high risk of developing arthritis based on a prediction rule with clinical parameters. Synovial thickening on US predicted clinical arthritis development at the patient level in seropositive patients with arthralgia when MTPs were excluded from the US assessment. Positive PD signs were infrequently seen in these at-risk individuals and was not predictive. In patients at intermediate risk of RA, US may help to identify those at higher risk of developing arthritis.